Copyright © 2019 by i-Logic Software support@i-logic.com

COMMUNICATIONS TROUBLESHOOTING GUIDELINES

Always start troubleshooting by sending from the machine control to DNC. The DNC software is much more flexible in how it receives data and will not issue an "alarm" like a machine control. The nature of the data received may help you identify the source of the problem. Follow these steps if you are having a problem communicating with the machine control. 1. With DNC in Terminal mode send a program from the machine control to the PC. If the machine "alarms": The cable may not be connected to the correct port at the machine control. Check the cable configuration at the machine end, particularly pins 6, 8, and 20. If the machine acts like it is prepared to send but "sits" continuously in send mode: A file will not be sent if the CTS line (line 4 or 5 depending on the machine configuration) is not asserted. The cable should have a jumper between pins 4 & 5, or lines 4 and 5 should pass through to their compliment lines on the computer end. If the machine looks like it is trying to send but you receive nothing: Check the cable. Pins 2 and 3 may need to be swapped to match the send/receive lines on the machine control with the receive/send lines on the computer. If hardware handshaking is being used and pins 2 and 3 need to be swapped pins 4 and 5 will also need to be swapped. Check to see that the correct port has been selected. A quick test is to unplug the cable while trying to send. If an alarm is shown, then the correct port is being addressed. Check the DNC communications parameters to be sure the correct COM port has been selected. Try sending to DNC from another machine control or another computer to verify the COM port is not defective. If "garbage" prints out on the computer screen while receiving: The communications parameters are probably mismatched. Check to see that the data types (ISO, EIA, or ASCII) match. Many machines have a parameter or setting to select between EIA and ISO. Then check the baud rate. Other possible sources of "garbage" are long cables, cables with weak connections, cables running near EMF sources, or ground faults. 2. Once data has been successfully received most cable, machine parameters, and COM port configuration problems have been eliminated. Now send from DNC to the machine control. If DNC appears to send the file but the machine acts like it is not receiving: Check the file contents. Perform the initial tests with a file which has been received from the control, not one generated on your CAD/CAM system. Some controls require an end of block at the beginning of the file or require a program qualifier (like 02213) at the beginning of the file. Others require a M30, M02, %, or END at the end of the file. If a partial program is received, blocks of data appear to be dropped, or the machine issues a data overflow alarm: Check to make sure handshaking has been properly enabled. If the cable uses only lines 2,3 and 7 select X-ON/X-OFF protocol. (Also referred to as Software Handshaking or DC1/DC3 control codes.) If the machine does not support software handshaking use a cable with pins 4 and 5 connected. This will enable CTS/RTS handshaking.
Troubleshooting
Serial

COMMUNICATIONS TROUBLESHOOTING

GUIDELINES

Always start troubleshooting by sending from the machine control to DNC. The DNC software is much more flexible in how it receives data and will not issue an "alarm" like a machine control. The nature of the data received may help you identify the source of the problem. Follow these steps if you are having a problem communicating with the machine control. 1. With DNC in Terminal mode send a program from the machine control to the PC. If the machine "alarms": The cable may not be connected to the correct port at the machine control. Check the cable configuration at the machine end, particularly pins 6, 8, and 20. If the machine acts like it is prepared to send but "sits" continuously in send mode: A file will not be sent if the CTS line (line 4 or 5 depending on the machine configuration) is not asserted. The cable should have a jumper between pins 4 & 5, or lines 4 and 5 should pass through to their compliment lines on the computer end. If the machine looks like it is trying to send but you receive nothing: Check the cable. Pins 2 and 3 may need to be swapped to match the send/receive lines on the machine control with the receive/send lines on the computer. If hardware handshaking is being used and pins 2 and 3 need to be swapped pins 4 and 5 will also need to be swapped. Check to see that the correct port has been selected. A quick test is to unplug the cable while trying to send. If an alarm is shown, then the correct port is being addressed. Check the DNC communications parameters to be sure the correct COM port has been selected. Try sending to DNC from another machine control or another computer to verify the COM port is not defective. If "garbage" prints out on the computer screen while receiving: The communications parameters are probably mismatched. Check to see that the data types (ISO, EIA, or ASCII) match. Many machines have a parameter or setting to select between EIA and ISO. Then check the baud rate. Other possible sources of "garbage" are long cables, cables with weak connections, cables running near EMF sources, or ground faults. 2. Once data has been successfully received most cable, machine parameters, and COM port configuration problems have been eliminated. Now send from DNC to the machine control. If DNC appears to send the file but the machine acts like it is not receiving: Check the file contents. Perform the initial tests with a file which has been received from the control, not one generated on your CAD/CAM system. Some controls require an end of block at the beginning of the file or require a program qualifier (like 02213) at the beginning of the file. Others require a M30, M02, %, or END at the end of the file. If a partial program is received, blocks of data appear to be dropped, or the machine issues a data overflow alarm: Check to make sure handshaking has been properly enabled. If the cable uses only lines 2,3 and 7 select X-ON/X-OFF protocol. (Also referred to as Software Handshaking or DC1/DC3 control codes.) If the machine does not support software handshaking use a cable with pins 4 and 5 connected. This will enable CTS/RTS handshaking.
Troubleshooting
Serial
Copyright © 2019 by i-Logic Software support@i-logic.com